fix(CircularProgressIndicator.adaptive): strokeWidth default value (flutter#165370)

fix: flutter#165294

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- [x] I read the [Contributor Guide] and followed the process outlined
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we expect every widget to implement].
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- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
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Author: StanleyCocos

packages/flutter/lib/src/material/progress_indicator.dart

@@ -744,7 +744,7 @@ class CircularProgressIndicator extends ProgressIndicator {
     super.value,
     super.backgroundColor,
     super.valueColor,
-    this.strokeWidth = 4.0,
+    this.strokeWidth,
     super.semanticsLabel,
     super.semanticsValue,
     this.strokeCap,

packages/flutter/test/material/progress_indicator_test.dart

@@ -433,6 +433,30 @@ void main() {
     expect(find.byType(CircularProgressIndicator), paints..arc(strokeWidth: 16.0));
   });
 
+  testWidgets('CircularProgressIndicator.adaptive stroke width', (WidgetTester tester) async {
+    await tester.pumpWidget(const CircularProgressIndicator.adaptive());
+
+    // The default strokeWidth is 4.0
+    expect(find.byType(CircularProgressIndicator), paints..arc(strokeWidth: 4.0));
+
+    final ThemeData themeData = theme.copyWith(
+      progressIndicatorTheme: const ProgressIndicatorThemeData(strokeWidth: 10.0),
+    );
+    await tester.pumpWidget(
+      Theme(data: themeData, child: const CircularProgressIndicator.adaptive()),
+    );
+
+    // Get the theme’s strokeWidth.
+    expect(find.byType(CircularProgressIndicator), paints..arc(strokeWidth: 10.0));
+
+    await tester.pumpWidget(
+      Theme(data: themeData, child: const CircularProgressIndicator.adaptive(strokeWidth: 16.0)),
+    );
+
+    // The strokeWidth parameter should override the theme’s strokeWidth.
+    expect(find.byType(CircularProgressIndicator), paints..arc(strokeWidth: 16.0));
+  });
+
   testWidgets('CircularProgressIndicator strokeAlign', (WidgetTester tester) async {
     await tester.pumpWidget(Theme(data: theme, child: const CircularProgressIndicator()));
     expect(